Boxer cv boot xref

Hi all,

Does anyone have first-hand experience using a Porsche / Lobro part for the CV boots on a Boxer? I've purchased boot kits from Maranello Classic Parts and Superformance in the past, and they've both failed prematurely. Looking to go with a Lobro part this time around, hoping the quality will be better.

As an exercise, I bought another kit from Superformance, and a few Lobro parts that have come up in various xref threads. I then took a few measurements:

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Lobro 300508 is the P/N that comes up most often, but as you can see, it's a bit different than the Superformance part.

Thoughts?

 

Good day Robert,

I will see if I can dig up where I bought mine and a part number, but I remember that the box did list Porsche's as being one of the manufacturers that the boots could be used on. These boots have lasted around 15 years and only recently noticed that the header heat is affecting their shape. I cannot recall, but have you tried to reduce the area heat temps? I had my headers ceramic coated, but also wrapped the boots with thermal wrap...both of which I am sure extended the boot's life.

Cheers,

Sam

 

My set only lasted a very short period of time after an engine out rebuild. Switched to a silicon set that have lasted for the past 5 years so far without issue. You can Google them, there are plenty of options.

 

I haven't yet done anything in that area to reduce temps. I was considering wrapping the headers in a ceramic fiber "blanket", but I have a few other projects to get through before I start tackling the headers.

I ended up chickening out on the Lobro boots, and installed the Superformance boot since it was dimensionally the closest to what I measured on the CV.

I might look into the "aero" or "high-speed" variants for next time.

https://www.pegasusautoracing.com/productdetails.asp?RecID=5549
https://www.race-parts.com/gkn-108mm-od-size-15-cv-tripode-joint-fast-boot?gQT=1


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I have the same issue with the rubber boots bought from our normally trusted Ferrari spare parts vendor(s). I'm about to change out the boots on my 308 for the third time in 11 years and I haven't driven the car much. On the 308 heat is not that big of a problem. To me it looks more like the rubber simply disintegrates over (short)time due to the oil in the grease. I wonder if they have the same issue with quality in the Porsche world?

Best, Peter

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I believe these will fit both the 308 and 512:

DRIVESHAFT BOOT (4 PCS)

Pricy but Cicognani have never let me down and I got a set of these on my 246 still running strong after 8 years of fairly regular driving.

Best, Peter

 

That's pricy, but worth it if they hold up. It's a job I don't particularly care for doing often. The description doesn't say the diameters, but if the picture is anything to go by, the shaft diameter looks more correct than the Porsche parts I ordered. I'll check them out, thanks!

 

Respectfully, what of the rear header? I've changed mine a few times in 39 years ownership. And the front header cooked one starter solenoid. I'm a fan of (not that it is a total cure) opening the engine deck after a drive to further allow the hot air to rise, and draw in cooler air from below to help some of these parts.

Here's a thought, based on who-knows-what...Boots that I have had short function from might be NOS, and sitting on a shelf somewhere, maybe next to some ozone generating equipment???

BTW: That picture looks like a brand new rubber part - except for the bad tear.

 

Cool find! It says the max joint angle travel is limited to 6º, (or ±3º). Is that enough?

 

When I was digging for CV joints and interchangeability, I recall BMW 635 and Porsche 930 boots & CV joints being on the list.

 

There are 2 torn boots out of 4 and they are all looking good until you examen them closely. The rubber has NO mechanical strength left and I can pull the boot's apart with hardly any force. I'm now going for my third set and will like to so something differently since I'm tired of cleaning up the grease mess in the engine bay and all the other extra hard work associated with removal of the shafts, cleaning and repacking the bearings etc. Most boots sold today most be newly produced aftermarket products - My best guess is that the quality of the rubber compound + lack of dimensional control during the casting process is the main issue here.

Best, Peter

 

I hear you on the mess. No fun at all. Especially when we are trying to keep the cars pristine.

I haven't done a 'CV boot' job in a while and sounds like I'm lucky as more re-popped parts are screwing things up. For my work, I have had a few polymer substitutes for rubber which have poor performance. Very frustrating. Last boots I got, I think were from Dennis McCann (Tom Vail) or Ted Rutland. I like the idea of the Pegasus boots because I have great experiences of great service & high-quality stuff from them, and I really like that they provide products to racers. The stuff gets used under harsh conditions. My only concern on those CV boots is the angle limitation. I have never measured the axle 'droop' angle when the car is lifted. This might destroy those CV boot cover shells in a big hurry. travel is limited to 6º, (or ±3º) Got me curious now, as sounds like a nice alternative to try.

 

https://www.bing.com/ck/a?!&&p=e8d0a188a9889ee03aa6da7b7a8dbca7a544252a211298cfd5d4012281e47f97JmltdHM9MTc0NjQ4OTYwMA&ptn=3&ver=2&hsh=4&fclid=22a2d9e6-77f3-60fb-2e85-ccc4767061cc&u=a1aHR0cHM6Ly93d3cucnViYmVyYW5kc2VhbC5jb20vaXMtdGhlcm1vcGxhc3RpYy1iZXR0ZXItdGhhbi1ydWJiZXIv&ntb=1

Thermoplastic elastomers (TPEs) are versatile materials that combine the elastic properties of rubber with the processing advantages of plastics. As thermoplastics, they can be melted and re-molded without chemical cross-linking, making them easy to process and recycle. TPEs can be used for applications requiring flexible, rubber-like parts with simplified manufacturing, but they generally offer lower mechanical strength, chemical resistance, and heat stability compared to thermoset rubbers.

In contrast, vulcanized rubbers (such as natural rubber, EPDM, or SBR) are thermoset materials. They undergo a curing process (typically with sulfur or peroxides) that creates permanent cross-links between polymer chains. This results in superior elasticity, abrasion resistance, and durability under high stress or elevated temperatures. Vulcanized rubber is still preferred in demanding applications like automotive tires and suspension bushings. However, over time, even vulcanized rubber degrades due to oxidation, UV exposure, and thermal aging.



(Yeah- - - - what 'he' said,,,Thanks Google! )

Sounds to me like we need that 'better' material. BTW, I can't always tell the difference. Usually TPE is a tad shinier,, and maybe smoother & darker black. There is a smell associated with rubber that's distinctive. But I would expect this could be missed.


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